Hello.

I needed a streaming template engine for a web app I'm building that works in Node.js, the browser, and service workers. Existing solutions like flora-tmpl were great for Node.js, but I needed something smaller and compatible with all environments. So, I created whatwg-flora-tmpl (name pending), a lightweight library based on the WhatWG Streams API. It uses template literals, handles dynamic content, and even supports nested streams. The example code demonstrates how it can be used to render HTML responses piece by piece instead of waiting for all data, significantly improving perceived performance. It's particularly useful for responses generated in service worker fetch events. Big thanks to Matthew Phillips, the creator of flora-tmpl, which served as the inspiration for this project.